This invention relates generally to thermoformed containers for foods or other articles, and in particular, to a container having a ventilation system, integrally formed handles, and an embossed bottom surface for retaining liquid with surface tension forces.
In many grocery stores and restaurants, particularly quick service restaurants, deli counters, or rotisserie/fried chicken stations, various food products are typically not served to the customer open on a plate immediately after being cooked. Rather, the food products are placed into individual containers so that each container can be handled, stored, reheated, or packaged in a bag, easily and conveniently. After cooking but before being served, the food products may be packaged and held in a holding area either at the store, during transport, or at home for a short period of time. This is especially true when a quick service restaurant or deli prepares and pre-packs a number of food products in anticipation of the traditional busy periods of lunch and dinner.
During this holding period before being served, certain food products can undergo changes in temperature, appearance, texture, and flavor. For example, the edges of hamburgers may get relatively cold and hard, or french fries may soak up vegetable oil which remains on their surfaces after cooking, pizza may become soggy, roasted chicken may dry-out, and fried chicken may lose its crunchiness. These changes in appearance and flavor tend to decrease customer satisfaction with these food products. Also, the efficiency with which food products can be served during busy hours is decreased as foods are not capable of being pre-packaged for fear of these unappealing changes. The decreased temperature and quality of appearance, texture, and flavor make these food products less appetizing.
It is also known that certain food products, such as fried chicken, emit moisture or water vapor along with latent heat stored in the chicken due to cooking and heating. At least a portion of this latent heat and moisture can condense on and be reabsorbed by the chicken itself, making the fried chicken soggy, less crispy, and tough to chew. Also, the water vapor can condense on the interior surfaces of the container and drip down towards the bottom of the container for the bottom pieces of fried chicken to absorb. If air circulation adjacent to and around the chicken is poor, the water reabsorption by the chicken increases since the latent heat and the resultant water vapor is further prevented from circulating away from the chicken. Further, if air from inside the container is not allowed to be exchanged with the air from outside the container, condensation of the water vapor on the inside of the container is more likely. Although a relatively small amount of water vapor escapes from the chicken and condenses, or is prevented from circulating away from the chicken, this amount may be enough to make the chicken undesirable.
After the water vapor condenses on the surface of the container and migrates to the bottom of the container, it mixes with the residual grease and juices that have exuded from the food product. After cooling and sitting for a period of time in such fluid, a piece of fried chicken, for example, may lose its delicious batter as it is lifted from the container with the delicious batter or breading remaining glued to the bottom surface. Also, after sitting in its own soup of grease, moisture, and meat juice, a piece of food product may become half-soaked with such fluid. Hence, there is also a need for containers that are more efficient in preventing excess grease and moisture from contacting the food.
Numerous attempts have been made to provide a container which prevents condensation from the food product from being reabsorbed. U.S. Pat. No. 5,423,477 to Valdman et al. issued Jun. 13, 1995, discloses a pizza box which incorporates a cover coated with a moisture absorbing inner layer of starch.
Also, a wide variety of container inserts have been developed to improve the quality of food especially when cooked in a microwave oven. For instance, it is known to place a fluid absorbent pad within a package for absorbing food by-products such as moisture and grease exuded from food during cooking in a microwave oven as shown in U.S. Pat. No. 4,873,101 issued to Larson et al. on Oct. 10, 1989. Such pads must not only provide a sufficient capacity for the quantity of food by-products produced during cooking, but also, must withstand the elevated temperatures required to adequately heat the precooked foods without degradation.
Other patents describe ways to exchange air between the interior of the container and the outside air to allow water vapor to escape. For example, U.S. Pat. No. 3,335,846, issued to R. E. Mills on Aug. 15, 1967, describes a container for pizza having a series of venting channels permitting such an exchange. The cover in this container is provided with one or more openings so that vapors from the interior of the container may be vented to the atmosphere.
One difficulty with prior art containers designed to keep moisture away from heated food is that the specialized coatings and layered construction make the containers both prohibitively expensive and difficult to manufacture. Although these techniques may have been helpful in preventing certain food products from becoming soggy, an improved container is desired.
Other problems with prior art containers, such as the visibility of grease and moisture, the spillage of fluid through venting apertures, and the inefficiencies associated with pre-packing, are discussed below.
There is a need for hiding the resulting fluid by-product, especially the fattening grease, from the consumer. Traditionally, bucket-type containers or fold-out boxes made from paperboard or other easily formed low-cost and grease absorbing material have been used in the market. When using paper buckets or fold-out paper boxes, the problem is compounded when the food product is allowed to sit inside the container. After a period of time, grease begins to soak through and stain the container revealing the food""s high-fat content. Such a container, much less its contents, quickly becomes unappealing to the fat-conscious consumer.
Another problem is the danger of spillage. During the holding period and, in particular, during transport, food juices may spill from the container and stain clothing and upholstery. Hence, preventing run-off of the food juices is of primary importance, especially if the container has vent openings large enough to permit food and juice to pass.
Furthermore, pre-packing frequently ordered food product can minimize wage labor time, especially during busy dining hours. However, using opaque paperboard containers leads wary consumers to re-open and check prepackaged containers for the right order. This inconvenience has increased demand for food packages that will attractively display and allow the consumer to view a substantial portion of the food product while at the same time providing for convenience in handling.
The present invention is a thermoplastic container. In accordance with one embodiment, the container includes a base having a bottom, a pair of opposing side walls and a pair of opposing end walls. The side walls and end walls extend upwardly from the bottom, and the end walls extend between the side walls. A rim encompasses an upper edge of the side walls and end walls and extends laterally outwardly therefrom. The bottom also includes a plurality of depending wells sufficiently small to retain a volume of fluid in the wells via capillary action or surface tension forces such that the volume of fluid therein does not flow out when the base is tilted or turned upside-down. Each of the wells has an interior surface area. The ratio of the volume of fluid to the interior surface area is in the range of approximately 2.8xc3x9710xe2x88x922 in to 3.8xc3x9710xe2x88x923 in.
In accordance with another embodiment, the container includes a base having a bottom, a pair of opposing side walls and a pair of opposing end walls. The side walls and end walls extend upward from the bottom, and the end walls extend between the side walls. A base rim encompasses an upper edge of the side walls and end walls and extends laterally outwardly therefrom. The rim has an integrally formed outer flange and a pair of opposing anchoring portions. The outer flange includes a pair of opposing handle segments, each having a pair of generally parallel hinged portions and a beaded graspable portion extending between the hinged portions. The hinged portions are rotatably connected to respective anchoring portions for upward and downward swinging movements. The handle segments include means for releasably engaging the handle segments to each other. Each of the hinged portions have at least one upwardly extending rib segment extending upwardly from an upper surface of the associated hinged portion, at least one downwardly extending rib segment extending downwardly from a lower surface of the associated hinged portion, and at least one integral hinge forming a definite bending point.
In accordance with yet another embodiment, the container includes a base having a bottom, a pair of opposing base side walls, a pair of opposing base end walls, and a base rim. The base side walls and base end walls extend upward from the bottom, and the base end walls extend between the base side walls. A base rim encompasses an upper edge of the base side walls and base end walls and extends laterally outwardly therefrom. The base rim has an upwardly protruding elongated rib with base venting notches intermittently interrupting the upwardly protruding rib. The container further includes a cover having a top, a pair of opposing cover side walls, a pair of opposing cover end walls, and a cover rim. The cover side walls and the cover end walls extend downward from the top, and the cover end walls extend between the cover side walls. The cover rim encompasses a lower edge of the cover side walls and the cover end walls and extends laterally outwardly therefrom. The cover rim has a downwardly protruding rib with cover venting notches intermittently interrupting the downwardly protruding rib. The cover venting notches are aligned with respective base venting notches and form respective vent openings when the cover is secured atop the base.